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arXiv · 1512.00954

Renormalization Scheme Dependence in b->u Semileptonic Decays

D. G. C. McKeon
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Abstract

After reviewing how the renormalization group equation can be used to sum logarithmic corrections to the decay rate for the semi-leptonic process b->u when using minimal subtraction, we consider renormalization scheme dependence for this calculation when employing this renor- malization scheme. In this calculation, an ambiguity resides in the running strong coupling and in the running b quark mass. The ambiguity usually associated with the renormalization mass scale mu is shown to cancel. It is demonstrated how in one renormalization scheme, there are only leading-log contributions to this decay rate. Another choice of renormalization scheme results in the decay rate being expressed in terms of the two-loop contribution to the beta-function associated with the strong coupling and the one-loop contribution to the anomalous mass dimension as well as a set of renormalization scheme invariant parameters.

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D. G. C. McKeon. 2015-12-03. Renormalization Scheme Dependence in b->u Semileptonic Decays. https://arxiv.org/abs/1512.00954

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